Fibrous mats, webs and blankets can be made by spinning molten materials like glass, slag, rock and various thermoplastic polymers and copolymers and attenuating the fibers to a desired average or mean diameter with mechanical forces or by jet blasts of air and/or combustion gases. Such processes are disclosed in U.S. Pat. No. 4,058,386 and RE030192, the disclosures of which are incorporated herein by reference, and many patents on processes similar to these patents. It is also known to make glass fiber insulation by forming primary fibers and then attenuating the primary fibers into fine insulation fibers using jet blast attenuation as disclosed in U.S. Pat. No. 5,882,372, the disclosure incorporated herein by reference, and in patents covering similar processes. It is also known to produce mat or webs from above type fibers and/or from fibers made from molten material by passing the molten through orifices, with or without nozzle tips, to form primary fibers and then to attenuate the still soft fibers by mechanically pulling or pulling with one or more rapidly moving gaseous streams to the desired diameters followed by collecting the fibers, wet or dry, onto a moving permeable belt. Also, numerous other systems and methods are known for forming fibrous mats, webs and/or blankets such as those wet or dry systems/methods used to make various kinds of paper, carding and lapping, and inclined wire wet laid nonwoven mat forming.
In the processes of making fiber glass insulation products in web, blanket or batt forms, usually the fibers have average fiber diameters of less than 10 microns, more typically less than about 5-6 microns and most typically in the range of about 3 to about 5 microns. The fibers are bonded together in the final product by intertwining by needling or water jets or with a cured resin binder, the latter being applied as an aqueous binder to the fibers soon after they are formed. The cured resinous binder forms a rigid matrix that is often broken when the mat, web or blanket, bat is cut, compressed for packaging, etc. or torn during manufacturing or application or use. Regardless of the system and method for forming the fibrous mat, web and/or blanket, the products usually contain some portion of very short fibers, fiber chips and other dust as a result, which tends fly off of the mat, web and/or blanket products during packaging, un-packaging, further processing, and/or use.
Normally a de-dusting agent is applied to the fibers and attenuated fibers prior to, during or after an aqueous binder is sprayed or otherwise applied onto the fibers prior to collecting the wetted fibers onto a permeable moving belt to form a thin mat, fibrous web or thick fibrous blanket, to reduce the dusting of the fibrous product. The mat, web and/or blanket is then usually passed through an oven, sometimes while being compressed by platens or moving belts, to control the thickness, to dry the product and to cure any binder on the fibers and in the fibrous product. The use of one or more de-dusting agents, applied in coarse particles or coarse droplets to the fibers before collection into an insulation mass is old, e.g. see U.S. Pat. No. 4,134,242, the disclosure incorporated herein by reference.
The glass fiber industry has used petroleum based oils, applied to the fibers in amounts typically of about 1 wt. percent of the final product to minimize or eliminate shedding of the short fibers, chips and dust from the fibrous products. A widely used petroleum oil for this purpose Brightstock 150 type oil available from Sun Oil Company having the tradename of SunPar™2280, having a typical viscosity of 480 centistokes at 40 degrees C. and a flash point of 304 degrees C. minimum. The
de-dusting petroleum oil is applied to the glass fibers soon after they are formed (often included with the aqueous binder) and then the fibers, in mat, web and blanket forms, are exposed to temperatures up to about 316 degrees C. in ovens to dry and cure the binder. During the curing, low molecular weight components of the petroleum oils de-dusting agent(s) are driven off and condense on cooler parts of the oven and exhaust fans and ducts. These volatiles and condensate cause undesirable emissions that usually must be abated, and more importantly, cause fires in the oven or exhaust ducts, the latter being both dangerous and very costly. Also, changes in the petroleum industry are reducing the availability of Brightstock type oils that are suitable as de-dusting agents. Oven and oven duct fires are frequent events in glass fiber insulation process lines. When a fire occurs, the line must be shut down immediately so the fire can be extinguished. This causes loss of production, scrap, and further maintenance downtime after the fire is extinguished. Extinguishing the fires is also dangerous as the oven and exhaust ducts are very hot and people can get burned by the fire, hot metal parts and steam. While the cost of a typical oven or exhaust duct(s) fire is very high, more importantly, it creates a situation where people fighting the fire can be injured. Also, it is possible in most oven fires for the fire to extend beyond the oven or oven ducts to other parts of the manufacturing line and the plant.
Fibrous mats are also produced by a process known as dry laid or wet laid processes in which fibers dispersed in air or water are laid onto a moving permeable belt moving over one or more suction boxes to remove the air or water to form a fibrous web. An aqueous binder and de-dusting agents are then applied to the wet or dry fibrous web in conventional ways and, after removing any excess binder and water, the wet, bindered fibrous web is carried through an oven to dry remove the water and to cure the binder in the mat. Such processes are disclosed in (add wet and dry laid mat process patents).
There is a need for an alternative de-dusting agent, a method of making glass fiber products containing an effective alternative de-dusting agent(s) and the products so produced.